linux-kernel - [PATCH v1 2/7] serdev: add dev_pm_domain

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <f976766cd499c8d7053a1f442aba1494b4d3314f.1522736996.git.sean.wang@mediatek.com>
Date:   Tue, 3 Apr 2018 15:15:52 +0800
From:   <sean.wang@...iatek.com>
To:     <robh+dt@...nel.org>, <mark.rutland@....com>,
        <marcel@...tmann.org>, <johan.hedberg@...il.com>
CC:     <devicetree@...r.kernel.org>, <linux-bluetooth@...r.kernel.org>,
        <linux-arm-kernel@...ts.infradead.org>,
        <linux-mediatek@...ts.infradead.org>,
        <linux-kernel@...r.kernel.org>, Sean Wang <sean.wang@...iatek.com>,
        "Rob Herring" <robh@...nel.org>,
        Ulf Hansson <ulf.hansson@...aro.org>,
        "Greg Kroah-Hartman" <gregkh@...uxfoundation.org>,
        Jiri Slaby <jslaby@...e.com>, <linux-serial@...r.kernel.org>
Subject: [PATCH v1 2/7] serdev: add dev_pm_domain_attach|detach()

From: Sean Wang <sean.wang@...iatek.com>

In order to open up the required power gate before any operation can be
effectively performed over the serial bus between CPU and serdev, it's
clearly essential to add common attach functions for PM domains to serdev
at the probe phase.

Similarly, the relevant dettach function for the PM domains should be
properly and reversely added at the remove phase.

Signed-off-by: Sean Wang <sean.wang@...iatek.com>
Cc: Rob Herring <robh@...nel.org>
Cc: Ulf Hansson <ulf.hansson@...aro.org>
Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Cc: Jiri Slaby <jslaby@...e.com>
Cc: linux-serial@...r.kernel.org
---
 drivers/tty/serdev/core.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c
index df93b72..c93d8ee 100644
--- a/drivers/tty/serdev/core.c
+++ b/drivers/tty/serdev/core.c
@@ -13,6 +13,7 @@
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
+#include <linux/pm_domain.h>
 #include <linux/serdev.h>
 #include <linux/slab.h>
 
@@ -330,8 +331,16 @@ EXPORT_SYMBOL_GPL(serdev_device_set_tiocm);
 static int serdev_drv_probe(struct device *dev)
 {
 	const struct serdev_device_driver *sdrv = to_serdev_device_driver(dev->driver);
+	int ret;
+
+	ret = dev_pm_domain_attach(dev, true);
+	if (ret != -EPROBE_DEFER) {
+		ret = sdrv->probe(to_serdev_device(dev));
+		if (ret)
+			dev_pm_domain_detach(dev, true);
+	}
 
-	return sdrv->probe(to_serdev_device(dev));
+	return ret;
 }
 
 static int serdev_drv_remove(struct device *dev)
@@ -339,6 +348,9 @@ static int serdev_drv_remove(struct device *dev)
 	const struct serdev_device_driver *sdrv = to_serdev_device_driver(dev->driver);
 	if (sdrv->remove)
 		sdrv->remove(to_serdev_device(dev));
+
+	dev_pm_domain_detach(dev, true);
+
 	return 0;
 }
 
-- 
2.7.4